Why do we Hindus eat with our hands? Is there a Vedic wisdom behind it? It is believed that our hands and feet are said to be the conduits of the five elements – fire, air, ether, earth and water. The Ayurvedic texts teach that each finger is an extension of one of the five elements.

The thumb is agni (fire) -- you might have seen children sucking their thumb, this is nature's way of aiding the digestion at an age when they are unable to chew;

the forefinger is vayu (air),

the middle finger is akash (ether - the tiny intercellular spaces in the human body),

the ring finger is prithvi (earth) and

the little finger is jal (water).

Source - Virtues of eating with hands: A Kerala banana leaf experience published in Business Standard